code: def regression_model():
      model = Sequential()
      model.add(Dense(64, activation="relu", input_shape=(13,)))
      model.add(Dense(64, activation="relu"))
      model.add(Dense(1, activation="linear"))
      return model
  
file_path: elephas/tests/conftest.py
imports: import pytest
  from tensorflow.keras import Sequential, Input, Model
  from tensorflow.keras.datasets import mnist, boston_housing
  from tensorflow.keras.layers import Dense, Activation, Dropout
  from tensorflow.keras.utils import to_categorical
label_desc: Use image node_id 2 for calling a global function with example usage: regression_model() and returns: model